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Biomedical subjects

B Wang

Publications and source records attributed to B Wang.

At least 631 records · Page 35Linked to original sources
PubMed1997

[Reconstruction of larynx with epiglottis and strip muscular flap after extended partial laryngectomy with T3 category].

Fourty patients with T3 glottic cancer were treated by extended partial laryngectomy with reservation of epiglottis and posterior part of thyroid cartilage. The operative defect was covered by bilateral strip muscular flap to reconstruct the sphincter function of the glottis. The 3-year survival rate was 82.5% (32/40) and 5-year survival rate 72.9%(27/37). The function of the reconstructed laryngx was satisfactory. The authors believe that the strip muscular flap is a good material for the reconstruction of the new laryngx because of its good blood supply and wide-range repairing capability.

Adult↗
PubMed1997

[Study on rearrangements of immunoglobulin genes in acute nonlymphocytic leukemia].

OBJECTIVE: To explore the mechanism of infidelity of immunoglobulin gene rearrangements in acute nonlymphocytic leukemia and its significance in genotyping of acute leukemia. METHODS: Immunoglobulin gene rearrangement was studied in 25 patients with acute nonlymphocytic leukemia in various stages by polymerase chain reaction. RESULTS: Immunoglobulin heavy chain gene rearrangements were detected in three of 25 patients, one of whom in complete remission was found to have tendency of relapse one month later. CONCLUSION: Lineage infidelity of immunoglobulin gene rearrangements does exist in acute nonlymphocytic leukemia, therefore, immunoglobulin rearrangements probably can not be regarded as an absolutely reliable marker for acute lymphocytic leukemia. Immunoglobulin rearrangements may have some significance in the detection of minimal residual disease of acute leukemia.

Adolescent↗
PubMed1997

[Serum tumor necrosis factor-alpha levels in non-Hodgkin's lymphoma patients and its relationship to prognosis].

OBJECTIVE: To explore the relationship of tumor necrosis factor-alpha (TNF alpha) with non-Hodgkin's lymphoma (NHL) and to evaluate clinical implication of serum TNF alpha. METHODS: Serum TNF alpha levals were measured by double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) in 76 NHL patients. Survival analysis was performed. RESULTS: Serum TNF alpha was increased in 55% newly diagnosed patients, and dropped to normal level on remission but increased again on relapse. Elevated TNF alpha levels of patients at diagnosis were significantly associated with Ann Arbor stage, bulky tumor and B symptoms, but weren't correlated to serum lactic-dehydrogenase (LDH) nor to beta 2-microglobulin (beta 2-MG). The survival period of patients with elevated TNF alpha levels was shorter than that of patients with normal TNF alpha levels. CONCLUSION: Elevated serum TNF alpha level is associated with high tumor burden and can be used as a prognostic marker.

Adult↗
PubMed1997

[Effects of total flavones of fructus Hippophae (TFH) on cardiac function and hemodynamics of anesthetized open-chest dogs with acute heart failure].

This study was carried out employing the model of dog with acute heart failure induced by phenobarbital natricum. It was shown that i.v. TFH 4.8 and 9.7 mg/kg could significantly increase CO, CI, + LVdP/dtmax and LVSP; shorten R-dP/dtmax in 9.7 mg/kg; raise - LVdP/dtmax, reduce LVEDP and T value; decrease MVO2I and TPVR; MAP and HR were not changed significantly. The results suggest that i.v. TFH can strengthen cardiac pump function and myocardial contractility in canine with heart failure; significantly improve myocardial diastolic function and hemodynamic performance; markedly decrease myocardia-used oxygen index and total peripheral vessel resistance, thus proving that TFH is good for heart failure.

Animals↗
PubMed1997

[Phenylethanoid glucosides from flos Buddlejae].

Four phenylethanoid glucosides were isolated from the flower of Buddleja officinalis. On the basis of specteral data, they were identified as salidroside(1), verbascoside(2), isoverbascoside(3) and echinacoside(4). Compounds 1, 3 and 4 were obtained from the plant for the first time. Compound 2 showed antibacterial and anticancer activities.

Drugs, Chinese Herbal↗
PubMed1997

[Two new flavanone glycosides from Glycyrrhizia inflata].

Two new flavanone glycosides having two chains of sugar moeity were isolated from the roots of Glycyrrhizia inflata Bat by repeated CC and HPLC. They were identified to be liquiritigenin-7-O-beta-D-apiofuranosyl-4'-O-beta-D-glucopyranoside(I) and liquiritigenin-7-O-beta-D-(3-O-acetyl)-apiofuranosyl-4'-O-beta-D- glucopyranoside (II) on the basis of chemical and spectroscopic methods.

Drugs, Chinese Herbal↗
PubMed1997

[Analysis of phenylethanoid glycosides of Herba cistanchis by RP-HPLC].

The Chinese drug "Rou Cong-rong" (Herba Cistanchis) is one of the commonly used drugs in Chinese traditional medicine. It is used to reinforce the vital function of kidney, especially that of the sexual organs and induce laxation, for the treatment of impotence, premature ejaculation in men, infertility, morbid leukorrhea, profuse metrorrhagia in women, and chronic constipation in the aged. This paper deals with the qualitative and quantitative analysis of phenylethanoid glycosides of four species and one variety of Genus Cistanche and 23 lots of commercial crude drugs of Herba Cistanchis by RP-HPLC. The results were as follows: the chemical constituents of Cistanche deserticola Ma, C. salsa (C. A. Mey) G. Beck, C. salsa var. albiflora P. F. Tu et Z. C. Lou and C. tubulosa were similar while those of C. sinensis were different from the others; the contents of echinacoside and acteoside of C. salsa, which were 2.13% and 1.51%, were the highest of the genus Cistanche. An ODS column (Alltima C18, 5 microns, 250 x 4.6 mm) was employed. Linear gradient elution of acetonitrile--1.5% acetic acid was used as mobile phase, and concentration of acetontrile was from 8% to 20% (0-60 min) in the qualitative analysis, and from 11.5 to 20% (0-35 min) in the quantitative analysis. The flow rate was 1.2 ml.min-1. The detection wavelength was set at 335 nm.

Chromatography, High Pressure Liquid↗
PubMed1997

[Preliminary study on differentiation of syndromes during HDT -6 degrees bed rest with traditional chinese medicine].

Differentiation of syndromes during 21 d HDT -6 degrees bed rest was made in 15 healthy young men. The results indicated that the subjects showed mainly deficiency of kidney-Yin, deficiency of Yin and hyperactivity of Yang, insufficiency of spleen-Qi and blood stasis in various degrees during the bed rest. The syndromes were most serious on the 3rd day, and then deficiency of kidney and deficiency of Yin and hyperactivity of Yang became mild gradually but insufficiency of spleen-Qi and blood stasis remained the same. The pulse condition was normal through the bed rest period

Bed Rest↗
PubMed1997

[The stress reaction induced by intensive noise exposure in rats].

To study the effects of sustained intensive noise on rats, fifty SD male rats were randomly divided into: control group and 1 d, 3 d, 7 d and 14 d noise exposure groups (120 dBSPL, broadband noise, 2 h daily). The results showed that after noise exposure, the ACTH level and the corticosterone level in serum increased, but the content of DA in diencephalon decreased, the weight of adrenal gland increased, while that of thymus and spleen decreased. Change of weight of adrenal gland and thymus became maximum after 7d-exposure. The ACTH level in serum and the content of DA in diencephalon decreased and the later reached the lowest value and the weight of adrenal gland and thymus returned to normal level after 14 d exposure. It indicated that the acute response began to decrease after 7d-exposure, and the response turned into a chronic inhibitory state after 14d-exposure.

Adrenal Glands↗
PubMed1997

[8-(N,N-diethylamino)-n-octyl-3,4,5-trimethoxybenzoate(TMB-8) reduced the elevation of [Ca2+]i induced by BHQ, NE and KCl in cultured single smooth muscle cells of the calf basilar artery].

The effect of 8-(N, N-diethylamino)-n-octyl-3,4,5-trimethoxybenzoate (TMB-8) on the elevation of [Ca2+]i induced by 2, 5-di (tert-butyl)-1, 4-benzohydroquinone (BHQ), norepinephrine (NE), KCl in cultured single smooth muscle cells of the calf basilar artery was studied by a system of measurement of AR-CM-MIC, using Fura-2/AM as a fluoresent indicator. In the presence of extracellular Ca2+ 1.3 mmol.L-1, the resting [Ca2+]i was not changed by TMB-8 (10, 30 and 100 mumol.L-1), but the elevation of [Ca2+]i induced by BHQ, NE and KCl were reduced by TMB-8 (30 mumol.L-1) significantly. In Ca2+ free Hank's solution containing EGTA 0.1 mmol.L-1, the resting [Ca2+]i was markedly reduced by TMB-8 (10, 30 and 100 mumol.L-1), and the increase of [Ca2+]i evoked by BHQ and NE was blocked completely by TMB-8 (30 mumol.L-1). The result suggested that TMB-8 inhibited the Ca2+ release from intracellular stores or increased the up-take of Ca2+ into sarcoplasmic reticulum and the inhibition of Ca(2+)-influx from extracellular site may be an indirect machanism.

Animals↗
PubMed1997

[Effect of TMB-8 on the increase of intracellular free Ca2+ induced by NE and BHQ in dissociated single rat brain cell].

The inhibitory effect and mechanism of 8-(N, N'-diethylamino) octyl 3, 4, 5-trimethoxybenzoate hydrochloride (TMB-8) on the elevation of single intracellular free Ca2+ concentration ([Ca2+]i) induced by High K+, Norepinephrine(NE) and 2, 5-Di(tert-butyl)-1, 4-benzohydroquinone (BHQ) in dissociated single rat brain cells were studied. The changes of [Ca2+]i were reflected by the fluorescent indicator, Fura-2/AM, employed. In the absence of extracellular Ca2+, Ca-free Hank's solution, preincubation with TMB-8 (10, 30 mumol.L-1) for 20 min significantly decreased the resting [Ca2+]i from 79 +/- 13 nmol.L-1 to 65 +/- 11 and 61 +/- 6 nmol.L-1, respectively. [Ca2+]i were markedly increased by NE and BHQ and reduced significantly to control level by TMB-8. On the other hand, when the cells were incubated in Hank's solution containing Ca2+ 1.3 mmol.L-1, TMB-8(30, 100 mumol.L-1) suppressed the increase of [Ca2+]i induced by NE (0.0001-0.1 mumol.L-1). TMB-8 showed no significant effect on [Ca2+]i elevation induced by KCl and BHQ in Hank's solution containing Ca2+ 1.3 mmol.L-1. These results indicate that TMB-8 reduced [Ca2+]i via increase of the sarcoplasmic reticulum (SR) sequestration, which blocked the release of intracellular store from the SR. However, the inhibitory effect of TMB-8 on Ca-influx from extracellular medium seems to be an indirect action from the saturation of SR with calcium.

Animals↗
PubMed1997

[GM-CSF regulates the Vp16 induced leukemic cell apoptosis].

OBJECTIVE: To explore the regulatory effects of granulocyte-macrophage colony stimulating factor (GM-CSF) on the apoptosis of leukemic cells induced by Vp16. METHODS: High expression retrovirus vector, N2A/CMV/GM-CSF, was constructed and transferred into human leukemic cell line HL-60, and Vp16 (final concentration 10microg/ml) was administered to transferred or nontransferred HL-60 cells. RESULTS: After Vp16 treatment, characteristic changes for apoptosis emerged in HL-60 cells. However, these findings did not emerge in GM-CSF gene transferred HL-60 cells. CONCLUSION: GM-CSF can suppress the leukemic cell apoptosis induced by Vp16.

Apoptosis↗
PubMed1997

[Relationship between bcl-X(L) expression and sensitivity to chemotherapy in acute myeloid leukemic cells].

OBJECTIVE: To investigate the characteristics and regulation of apoptosis in acute myeloid leukemic cells. METHODS: Flow cytometry, DNA electrophoresis and Northern blot were used to analyze the expression of bcl-X(L) before and after Vp16 treatment, and the relationships between bcl-X(L) expression and apoptotic sensitivity, clinical features and prognosis were also analyzed. RESULTS: Most of the leukemic cells from AML patients overexpressed bcl-X(L) mRNA. The expression of bcl-X(L) was still maintained high level after Vp16 treatment in patients with pretreatment overexpression. These patients were resistant to apoptosis, poor responsed to chemotherapy and associated with adverse prognostic features, such as high WBC counts, local leukemic infiltrations. Bone marrow cells from long-term remission AML patients and normal controls also showed bcl-X(L) downregulation after in vitro Vp16 treatment, but the apoptotic rates were lower than that in nonremissive AML. CONCLUSION: Overexpression of bcl-XL played an important role in leukemogenesis and drug resistance. Downregulation of bcl-X(L) was necessary but not sufficient to initiate apoptosis.

Adolescent↗
PubMed1997

[Surface photovoltaic spectroscopic investigation of Bacteriorhodopsin (BR)].

The surface photovoltaic spectra (SPS) of Bacteriorhodopsin-based films were systematically measured. The results show that the BR films are characterized by the specific photovoltaic effect. The SPS response of the BR films depends on the fabrication and humidity of the film. The intermediate M412 and O640 of BR are observed in the SPS of HEPES-containing BR film, indicating that HEPES has very important function to stabilize intermediate M412. The observations are explained in terms of the photocycle of BR and the mechanism of photovoltage generation.

Bacteriorhodopsins↗
PubMed1997

Induction of apoptosis in cultured midbrain cells from embryonic mice.

Midbrain cells from embryonic mice were cultured at a high cell density for 4 days to observe proliferation and differentiation. Results indicate that UVC radiation caused dose-dependent inhibition of their proliferation and differentiation. Inhibitory effects of UVC radiation (per unit dose) were greater on cell differentiation than on proliferation. The percentage of apoptotic cells in the groups irradiated with 15 J/m2 became significantly higher than the control level 2 h after irradiation. The percentage of apoptotic cells increased with time in a dose-associated fashion and reached a maximum at about 7.5 h after irradiation. Then it decreased with time and returned to the control level at about 30 h after irradiation. Metabolic inhibitors could postpone occurrence of intermediate apoptosis (>2 h, but <20 h) if they were added at suitable times after irradiation but failed to prevent a delayed apoptosis (>24 h). Results showed that UVC radiation induced intermediate apoptosis which could be postponed by metabolic inhibitors, and that UVC could also induce delayed apoptosis with the addition of metabolic inhibitors. The result that UVC radiation could induce intermediate apoptosis in the midbrain cells was different from previous data obtained using cells of an established cell line. The implications of the results for the understanding of the mechanism involved are discussed.

Animals↗
PubMed1997

CD3-epsilon overexpressed in prothymocytes acts as an oncogene.

BACKGROUND: Upon engagement of the T cell receptor for antigen, its associated CD3 proteins recruit signal transduction molecules, which in turn regulate T lymphocyte proliferation, apoptosis, and thymocyte development. Because some signal transducing molecules recruited by CD3-epsilon, i.e., p56lck and p59fyn, are oncogenic and since we previously found that overexpression of CD3-epsilon transgenes causes a block in T lymphocyte and NK cell development, we tested the hypothesis that aberrant CD3-epsilon signaling leads both to abnormal T lymphocyte death and lymphomagenesis. MATERIALS AND METHODS: Ten independently derived transgenic mouse lines were generated with four different genomic CD3-epsilon constructs. Mice either homozygous or hemizygous for each transgene were analyzed for an arrest in T lymphocyte development and for the occurrence of T cell lymphomas. RESULTS: Aggressive clonal T cell lymphomas developed at very high frequencies in seven mouse lines with intermediate levels of copies of CD3-epsilon derived transgenes. However, these lymphomas were not found when high copy numbers of CD3-epsilon transgenes caused a complete block in early thymic development or when a transgene was used in which the exons coding for the CD3-epsilon protein were deleted. Analyses of a series of double mutant mice, tgCD3-epsilon x RAG-2null, indicated that lymphomagenesis was initiated in lineage-committed prothymocytes, i.e., before rearrangement of the T cell receptor genes. In addition, the transgene coding for the CD3-epsilon cytoplasmic domain and its transmembrane region induced a T cell differentiation signal in premalignant tgCD3-epsilon x RAG-2null mice. CONCLUSION: The nonenzymatic CD3-epsilon protein acted as a potent oncogene when overexpressed early in T lymphocyte development. Lymphomagenesis was dependent on signal transduction events initiated by the cytoplasmic domain of CD3-epsilon.

Animals↗
PubMed1997

Coinfection and genetic recombination between HIV-1 strains: possible biological implications in Australia and South East Asia.

It has been recognised that human immunodeficiency virus (HIV) mutates rapidly and that nucleotide substitutions, deletions, insertions, and rearrangements resulting from recombination events are the main factors that result in variation of the HIV-1 genome. Together, these processes are actively contributing to the diversity and virulence of viral forms comprising the acquired immune deficiency syndrome (AIDS) pandemic. There are 9 HIV-1 subtypes recognised (A-H and O), based on the envelope region segments. Inter-subtype recombination has been already described, whereas intra-subtype recombination has been difficult to detect. In this study, we have identified in vivo genetic recombination between HIV-1 strains belonging to subtype B in a patient who presented both intravenous drug use (IVDU) and homosexual sex as risk factors. Genetic analysis of viral strains in the hypervariable V3 region of the envelope gene indicated the presence of three distinct sequence groups categorized according to their respective tetrapeptide motifs-GPGR, GLGR and GPGK. Detailed genetic and phylogenetic analyses suggested the recombination occurring only between sequence groups with GPGR and GPGK tetrapeptide motifs. These data suggest that coinfection with closely related strains can occur in vivo, and the generation of hybrid HIV-1 genomes via genetic recombination between subtype B strains can result in further antigenic diversity which may thwart diagnosis and future vaccine efforts. Since HIV-1 subtype B is still the most commonly found subtype around the globe, the hybrid genomes between different subtype B strains may result in epidemiologic shifts and altered pathogenesis.

AIDS-Related Opportunistic Infections↗